edX

Three years ago, Harvard University and MIT embarked on a unique experiment when they launched a nonprofit called edX. The start-up promised a free online education, with university-level classes for anyone living anywhere across the globe.

The buzz around open online courses - often free and occasionally for credit - is fading. But as tuition prices and student debt soar, online learning continues to grow. One of the largest providers of massive open online courses, or MOOCs, is Harvard and MIT's edX. Some 2.5 million people have signed up for these classes, ranging from the Introduction to Computer Science to The Ancient Greek Hero.

So what do most students get for completing one of these courses? New knowledge and maybe a certificate of completion, but no credit. WGBH’s On Campus caught up with a student-researcher who predicts colleges and universities will soon offer some form of credit for MOOCs.

After barely more than a year in business, opposite-coast rivals edX and Coursera have become two of the biggest higher-education organizations in the world, with a combined six million registered users drawn to the online teaching they provide.